Where Should I Zero the NMR Spectra of Dimethylacetamide in CDCl3?

[Chickenpoxpie]

Homework Statement

I have a spectra of the NMR, I'm just confused on where to `zero' the spectra at?

Homework Equations

The Attempt at a Solution

There are two peaks around zero in the spectra (one is bigger than the other but not by much). Also the two peaks are much much smaller than the peaks I know are Dimethylacetamide. I just don't know where to zero it.

Any help is appreciated

 

[chemisttree]

So, you didn't put any TMS in your CDCl3?

 

[Chickenpoxpie]

We used 3% TMA?